sortedIndex

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2023-12-01

Performs a binary search of this sequence, returning the lowest index where the given value is either found, or where it belongs (if it is not already in the sequence).

This method assumes the sequence is in sorted order and will fail otherwise.

Signature

Sequence.sortedIndex = function(value) { /*...*/ }

Sequence.sortedIndex = function sortedIndex(value) {
  var indexed = this.getIndex(),
  lower   = 0,
  upper   = indexed.length(),
  i;

  while (lower < upper) {
i = (lower + upper) >>> 1;
if (compare(indexed.get(i), value) === -1) {
  lower = i + 1;
} else {
  upper = i;
}
  }
  return lower;
}

Name	Type(s)	Description
value	*	The element to search for in the sequence.
returns	number	An index within this sequence where the given value is located, or where it belongs in sorted order.

Examples

Lazy([1, 3, 6, 9]).sortedIndex(3)                    // => 1
Lazy([1, 3, 6, 9]).sortedIndex(7)                    // => 3
Lazy([5, 10, 15, 20]).filter(isEven).sortedIndex(10) // => 0
Lazy([5, 10, 15, 20]).filter(isEven).sortedIndex(12) // => 1